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不公正的胜利

不公正的胜利

Epididymis cholesterol homeostasis and sperm fertilizing ability

作者： (法)伊曼纽尔·赛斯(emmanuel saez)，加布里埃尔·祖克曼(Gabriel Zucman)

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Asian Journal of Andrology 2011年第1期13卷 11-17页

作者： Fabrice saez Ouvrier and Joel R Drevet UMR GReD CNRS 6247 INSERM U931 Clermont Universite Equipe ＇Epididyme et maturation des gametes＇ Aubiere cedex 63171 France

Cholesterol, being the starting point of steroid hormone synthesis, is a long known modulator of both female and male reproductive physiology especially at the level of the gonads and the impact cholesterol has on gametogenesis. Less is known about the effects cholesterol homeostasis may have on postgonadic reproductive functions. Lately, several data have been reported showing how imbalanced cholesterol levels may particularly affect the post-testicular events of sperm maturation that lead to fully fertile male gametes. This review will focus on that aspect and essentially centers on how cholesterol is important for the physiology of the mammalian epididymis and spermatozoa.

关键词： cholesterol homeostasis epididymosomes fertility post-testicular maturation spermatozoa

Modelling die filling with charged particles using DEM/CFD

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Particuology 2012年第2期10卷 229-235页

作者： emmanuel Nkem Nwose School of Chemical Engineering University of Birmingham Birmingham B15 2TT UK

The effects of electrostatic charge on powder flow behaviour during die filling in a vacuum and in air were analysed using a coupled discrete element method and computational fluid dynamics （DEM]CFD） code, in which long range electrostatic interactions were implemented. The present 2D simulations revealed that both electrostatic charge and the presence of air can affect the powder flow hehaviour during die filling. It was found that the electrostatic charge inhibited the flow of powders into the die and induced a loose packing structure. At the same filling speed, increasing the electrostatic charge led to a decrease in the fill ratio which quantifies the volumetric occupancy of powder in the die. In addition, increasing the shoe speed caused a further decrease in the fill ratio, which was characterised using the concept of critical filling speed, When the electrostatic charge was low, the air/particle interaction was strong so that a lower critical filling speed was obtained for die filling in air than in a vacuum. With high electrostatic charge, the electrostatic interactions became dominant. Consequently, similar fill ratio and critical filling speed were obtained for die filling in air and in a vacuum.

关键词： DEMCFDElectrostaticsDie fillingPowder flowCohesionCharged particles

Systems Analysis of Vulnerability to Hydrometeorological Threats: An Exploratory Study of Vulnerability Drivers in Northern Zimbabwe

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International Journal of Disaster Risk Science 2019年第2期10卷 204-219页

作者： emmanuel Mavhura Department of Geography Bindura University of Science Education

Disasters result from complex interactions of hazards and vulnerability conditions. Reducing human exposure and sensitivity to threats can reduce disaster impact. Prior knowledge about community vulnerability levels is crucial to minimizing potential losses from future threats. Most vulnerability studies focus on high-impact disasters and their temporal and spatial analyses. Yet highfrequency, low-impact disasters have a cumulative potential to severely disrupt or damage socioeconomic *** is limited knowledge especially in the global south about the creation of vulnerability to hydrometeorological threats. Using a systems approach, this study explores ways in which communities in the northern semiarid tropics of Zimbabwe are vulnerable to hydrometeorological *** predominantly qualitative study used literature review, interviews, transect walks, and focus groups to gather data from selected samples involving smallholder farmers with in-depth knowledge about community vulnerability. The results show that the communities are vulnerable to multiple hydrometeorological threats due to multiple interacting factors including rainfed and floodbased farming, land tenure, topography, climate, and other socioeconomic conditions such as inadequate income sources and high poverty. In order to reduce vulnerability,this study provides five policy options for government and nongovernmental organization interventions, including the need to transform rural economies beyond the traditional rainfed and flood-based farming systems.

关键词： Community vulnerability Flood-based farming Hydrometeorological threats Rainfed agriculture Zimbabwe

Physico-chemical characterization of a farmland affected by wastewater in relation to heavy metals

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第3期9卷 366-372页

作者： emmanuel U. ONWEREMADU Department of Soil Science and Technology Federal University of Technology PMB 1526 Owerri Nigeria

This study investigated selected properties of soils affected by wastewater and its relationship with some heavy metals. A free survey technique involving target sampling was used in siting soil profile pits. Soil samples were collected based on horizon differentiation and analyzed using routine and special analytical techniques. Soil data were subjected to correlation analysis using SAS program. Results show that all heavy metals studied had values above critical limits in the polluted soils using known standards and that these biotoxic metals decreased with soil depths. Highly significant (P=0.01 and 0.05) relationships were established between investigated heavy metals and some soil properties, especially soil pH and organic matter. Further studies involving more edaphic properties, biotoxic metals and their bioaccessibility in crops growing on wastewater soils will surely enhance knowledge and management of these highly anthropogenically influenced soils of the study site.

关键词： Bioavailability Characterization Heavy metals Soil pollution Wastewater

A Unified Spatio-Temporal Framework of the Cuerno-Barabasi Stochastic Continuum Model of Surface Sputtering

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Communications in Theoretical Physics 2012年第7期58卷 165-170页

作者： Oluwole emmanuel Oyewande Department of Physics University of Ibadan

The nonlinear continuum model proposed by Cuerno and Barabasi is the most successful and widely acceptable theoretical description of oblique incidence ion sputtered surfaces to date and is quite robust in its predictions of the time evolution and scaling of interfaces driven by ion bombardment. However, this theory has thus far predicted only ripple topographies and rough surfaces for short and large scales, respectively. As a result, its application to the interpretation and study of nanodots, predicted by Monte Carlo simulations for, and observed in experiments of, oblique incidence sputtering is still unclear and, hence, an open problem. In this paper, we provide a new insight to the theory, within the same length scale, that explains nanodot formation on off-normal incidence sputtered surfaces, among others, and propose ways of observing the predicted topographies of the MC simulations, as well as possible control of the size of the nanodots, in the framework of the Cuerno-Barabasi continuum theory.

关键词： topographic phase diagrams surface nanostructures surface nanodots Cuerno-Barabasi model

The epididymal immune balance:a key to preserving male fertility

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Asian Journal of Andrology 2019年第6期21卷 531-539页

作者： Allison Voisin Fabrice saez Joel R Drevet Rachel Guiton Team Mechanisms of Posttesticular Infertility GReD LaboratoryCNRS UMR 6293-INSERM U1103 University of Clermont Auvergne Clermont-Ferrand 63001France

Up to 15%of male in fertility has an immuno logical origi n,either due to repetitive infections or to autoimmune resp on ses mainly affecting the epididymis,prostate,and *** observations and epidemiological data clearly contradict the idea that the testis confers immune protection to the whole male genital *** a consequenee,the epididymis,in which posttesticular spermatozoa mature and are stored,has raised some in terest in recent years when it comes to its immune mecha *** deed,sperm cells are produced at puberty,long after the establishment of self-toleranee,and they possess unique surface proteins that cannot be recognized as *** are potential targets of the immune system,with the risk of inducing autoantibodies and consequently male *** immunity is based on a finely tuned equilibrium between efficient immune responses to pathogens and strong tolerance to sperm *** processes rely on incompletely described molecules and cell *** review compiles recent studies focusing on the immune cell types populating the epididymis,and proposes hypothetical models of the organization of epididymal immunity with a special emphasis on the immune response,while also discussing important aspects of the epididymal immune regulation such as tolerance and tumour control.

关键词： epididymis immune response lymphocytes mononuclear phagocytes toleranee

Abiraterone acetate for prostate cancer： a new era ot hormonal therapies

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Asian Journal of Andrology 2011年第5期13卷 663-664页

作者： emmanuel S Antonarakis Johns Hopkins Sidney Kimmel Comprehensive CancerCenter Baltimore MD 21231 USA

Therapies targeting the androgen receptor （AR） axis have constituted the HolyGraft in the management of advanced prostate cancer for seven decades） These hormonal therapies have traditionally taken two main forms： those that suppress gonadal androgen synthesis （e.g., the gonadotropin releasing hormone agonists/antagonists, such as leuprolide）, and those that inhibit the AR directly （e.g., the anti-androgens, such as bicalutamide）. However, although the vast majority of patients with prostate cancer initiaUy respond favorably to androgen-ablative therapies （manifested by tumor regressions and symptomatic improvements）, all patients will eventually develop further disease progression after a median of 18-24 months. This transformed disease state, known as castration-resistant prostate cancer （CRPC）, is invariably fatal.

关键词： Enzyme mechanisms

Recent developments in the application of oil palm fibers in cement composites

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Frontiers of Structural and Civil Engineering 2020年第1期14卷 94-108页

作者： emmanuel Owoichoechi MOMOH Adelaja Israel OSOFERO School of Engineering University of AberdeenAberdeenAB243UEUK

Fibers obtained from different parts of the oil palm tree(Elaeis guineensis)have been under investigation for possible use in *** have been carried out investigating the engineering properties and possible applications of these ***,the experimental methods employed and the values of mechanical and physical properties recorded by various authors are *** has therefore become necessary to organize information which would be useful in the design of oil palm fiber cement composites and help researchers and engineers make informed decisions in further research and *** review provides information about fibers from different parts of the oil palm,their properties,enhancement techniques,current and potential application in cement composites.

关键词： broom cement composite concrete oil palm fiber Natural fiber-concrete sustainability